21620470042256 has 80 divisors (see below), whose sum is σ = 43696377002880. Its totient is φ = 10354105359360.

The previous prime is 21620470042243. The next prime is 21620470042261. The reversal of 21620470042256 is 65224007402612.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28929965 + ... + 29667891.

It is an arithmetic number, because the mean of its divisors is an integer number (546204712536).

Almost surely, 2^{21620470042256} is an apocalyptic number.

It is an amenable number.

21620470042256 is an abundant number, since it is smaller than the sum of its proper divisors (22075906960624).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21620470042256 is a wasteful number, since it uses less digits than its factorization.

21620470042256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 738792 (or 738786 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 41.

Adding to 21620470042256 its reverse (65224007402612), we get a palindrome (86844477444868).

The spelling of 21620470042256 in words is "twenty-one trillion, six hundred twenty billion, four hundred seventy million, forty-two thousand, two hundred fifty-six".